St Kilda's amusement park has had plenty of thrills and spills in its 98-year history.

ONE of the earliest attractions at Luna Park was ''Aunt Jemima's Washing Day'', which, according to one report, featured ''a Negro woman above a washtub who fell in when hit''. Visitors were also invited to gawk at ''Siamese twins'', a midget showgirl and a morbidly obese child billed as ''the world's fattest boy''.

An Australian soldier and female friend on Luna Park’s Jack and Jill slide in 1954.

Indeed. The amusement park, which opened 98 years ago today, has changed a lot over the years. Gone are the fondly remembered River Caves, Giggle Palace and Kaiser's Kitchen, where patrons were urged to throw crockery at an effigy of Kaiser Wilhelm II. The Big Dipper - which many baby boomers still search for - has also disappeared, as has the nausea-inducing Gravitron, a favourite of Generation Xers.

Yet the important bits remain: the smiley moonface entrance and the Scenic Railway, which is the oldest continually operating wooden roller-coaster in the world (and just one of two that requires a ride-on brake operator). And there are still plenty of opportunities to make yourself dizzy on the newer rides, including the Coney Island Drop Top, which opens today.

Mr Harrison, who started in 1990 as a rides operator, estimates that someone becomes ill every half-hour or so. ''We call it a 'code rainbow' over the radio,'' he says, ''and in [Sydney's Luna Park], they call it a 'protein spill'.''

While most St Kilda landmarks have a habit of burning down - the sea baths, the St Moritz Ice Rink, the pier kiosk and the Palace nightclub have all been lost to fire - Luna Park is still standing. ''But when you put a wooden roller-coaster next to the beach, it doesn't like it,'' Mr Harrison says. ''It's like the Sydney Harbour Bridge: by the time you're finished at one end, you have to start again at the other, which is why we have three full-time carpenters working on it.''

Bit by bit, these chippies replace each beam of wood with a new one, meaning that very little of the original structure still stands. But it's remarkably energy-efficient for such an ancient contraption. ''It gets towed up the top [via electric cables],'' Mr Harrison says, ''and then gravity does the rest. It basically operates through its own momentum.''

Is it still a magnet for young lovebirds?

''I'm well past that, so I have no idea,'' he chuckles. ''But I suppose we do get a lot of young ones, especially on Friday nights.'' In fact, there's a scientific explanation for why a roller-coaster ride is a good first date: it releases the same hormone that's triggered by falling in love.

Trucking magnate Lindsay Fox, a part-owner of Luna Park, recalls wooing his wife Paula there in 1960s. ''And I often get people telling me that their father proposed to their mother outside the entrance or on the carousel,'' he says, ''or that they had their first kiss in the River Caves.''

But this triangular patch of land wasn't always a romantic hot spot. Rather, it was a swamp - and also the location of the world's first feature film, The Story of the Kelly Gang. In 1906, an amusement park called Dreamland opened. Quickly dubbed ''Deadland'' by the Truth newspaper, it closed in 1909, sitting vacant until American proprietors relaunched it as Luna Park in 1912.

More than 20,000 people attended the opening, captivated by the thousands of ''electric lights''. But soon, there was trouble.

''A fine harvest has been gathered by pickpockets,'' The Age reported three days later, noting that one suspect had £44 on him when he was arrested.

Early photographs reveal the outfits deemed appropriate for a day of seaside frivolity back then: three-piece suits and top hats for men; while ladies braved the heat in corsets and neck-to-toe dresses.

By 1930, Luna Park had begun to attract ''the wrong classes of people to St Kilda'', according to The Argus newspaper. During World War II, the suburb became popular with American servicemen, whose debauched antics popularised the phrase ''behaving like an American sailor on shore leave''. As A Brief History of Melbourne's Luna Park puts it, ''Like the rest of St Kilda, Luna Park became heavily associated with sexual desire and loosening morals.''

But despite the suburb's evolution from wealthy exclusivity to drugs and prostitution - and now a bohemian-yuppie playground - its most famous landmark has remained popular throughout. Indeed, of the 81 Luna Parks that have existed around the world, Melbourne's is believed to be the oldest still in operation.

''We're in discussions at the moment about rebuilding the old-style Rotor, which was a bit like the Gravitron,'' Mr Harrison says. ''There are some rides that will never change, but we're also constantly looking to update.''